These dissections of flowers of Monotropsis odorata show the distinctive pale purple color of the petals, which are united into a bell-shaped tube. Ten stamens are present in the flowers, as can be seen from the upper flower, from which the petals have been removed.

The central parts of a flower of Monotropsis odorata. The stigma, which collects pollen, is sticky (here, it has collected some debris, unfortunately). The anthers have shed most of their pollen grains. The anthers shed the pollen grains through oval-shaped openings.

There are about 100 species of Orobanche (common name: broomrape) worldwide, mostly in temperate areas. Orobanche is a parasite on the roots of other plants. Orobanche has no chlorophyll. The flowers suggest flowers of penstemons, monkey flowers, or snapdragons, and Orobanche is closely related to those plants. However, Orobanche goes into a family, Orobanchaceae, that now also includes Indian Paint Brush (Castilleja), which is a green plant that parasitizes roots of other plants. Some species of Orobanche are rare, but some are common and even pests. Orobanche ramosa is a serious parasite on tomato plants in California.

Two plants of Orobanche fasciculata that have been excavated. Notice that the lower two-thirds of the plants is white: this portion of the plants is underground, and the upper one third of the plants appears above the soil surface. The leaves of these plants are narrow and cover the stems. Some of the leaves have turned brownish. Although white when first formed, the leaves can turn brown because of injury or even natural pressure as the flowers expand and push upward through the soil surface.

At the bases of these two plants of Orobanche fasciculata are roots; especially note the plant at the right. These roots belong to the Orobanche plants, but they have interconnections (not shown) with roots of host plants. Orobanche takes water, sugar, and other substances from host plants through their roots.

A flower of Orobanche californica, sectioned so as to show two of the four stamens. The pollen has mostly been shed from the pale yellow-colored anthers at this stage. The stigma is white and has two pointed flaps.

Ammobroma (Greek for "sand food") is the common name for this curious desert sand dune plant, a flowering plant parasitic on desert shrubs such as Tiquilia and Eriogonum. The only part of the plant normally visible above the sand surface is the inflorescence, which is 5 to 15 cm in diameter.

A face view of a flower of Pholisma sonorae. There are about twice as many flower parts as in the ordinary borages, such as forget-me-not and heliotrope. The color and shape of the flowers suggests that they might be pollinated by long-tongued bees, but no studies have apparently been done on that yet. The sepals turn dark brown very quickly. There are numerous light brown wooly hairs on the sepals.

A section of the edge of an inflorescence. From right to left: old flowers, the floral tube wilted by the bottom widens as seeds form; then a few open flowers; then, at left, the curled over portion of the inflorescence with unopened flowers, the sepals of which are purple.

A longitudinal section of an open flower, with some other flowers nearby. The tissues of Pholisma sonorae are white, but they turn brown with age or soon after being cut. This photograph shows the tubular nature of the Pholisma sonorae flower. The purple sepals are slender, and are covered with large numbers of hairs.

The underground portions of Pholisma sonorae are long, succulent stems that bear elongate leaves, some of which have been displayed in this portion of a stem dug up from the sand. If one dug deeply enough, one might be able to find where a root connection originally formed between the parasitic Pholisma sonorae plant and its host plant. However, sand continually sifts over Pholisma sonorae plants and buries them more deeply. We have no idea how many flowering stems might branch from one original plant. There is, however, a curious feature shown in this photograph. Apparently the leaves of Pholisma sonorae bear small root like structures on their outer surfaces. Are these indeed roots that make contact with roots of a host plant? They seem unlikely to be hairs of any sort, because the lennoid plants related to Pholisma sonorae have no hairs on underground leaves. However, no studies have been done on these structures, which do not appear to have been mentioned in literature on Pholisma sonorae.

The scientific name for Ammobroma is Pholisma sonorae--it was originally named Ammobroma sonorae, but it is now thought to belong to the genus Pholisma. Pholisma was said to be in the small family of parasitic plants Lennoaceae, but now Lennoaceae is considered a subfamily (Lennoideae) of Boraginaceae, the forget-me-not family. This is a smaller inflorescence, which looks doughnut-like in shape, but is actually funnel-shaped, the outer edges of the funnel rounded, and the center of the funnel filled with sand.

A larger inflorescence of Pholisma sonorae, showing the somewhat irregular shape. Pholisma sonorae grows in sand dunes of northwestern Sonora, Mexico ("El Gran Desierto") and adjacent California and Mexico. The name "sand food" derives from its apparent use by Sonoran natives as a source of food.

An inflorescence of Pholisma sonorae removed from the sand, with the sand shake from it reveals that the inflorescence is funnel shaped. The center is older; flowers are progressively younger toward the edge of the inflorescence.

Items posted on the Botanical Society of America's website by the author/creator are licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License. We value sharing, growing and learning together. In the spirit of fairness, we believe in the attribution of materials and ensuring the appropriate voices are in place when considering further use.